1. Field of the Invention
The invention pertains to dot matrix printers which print characters composed of dots and more particularly printers that are controlled electronically. Examples of such printers are those having a system for communicating information to a scanned medium which may utilize reflected light from a multifaceted rotating polygon or which may use a light emitting diode array to direct light to a photoreceptive surface. Other types of dot matrix printers include ink jet and thermal printers.
2. Description of the Prior Art
A recurring problem in dot matrix printing is to obtain refined characters, i.e., characters which give a good appearance. Various attempts have been made in the prior art to increase the quality of printing. For example, in U.S. Pat. No. 4,321,610, a matrix of overlapping dots is employed for the purpose of enhancing the quality of characters printed. This is defined in the patent as half space dot capability. In U.S. Pat. No. 4,149,071 means is provided to compensate for deterioration of modulation based on thermal effects on the light emitting elements so that a desired optical output waveform is obtained.